Foot-press for jewelers



(No Model.)

H. CHAPMAN.

Poo tPre'ss'for Jewel ers, No. 241,617. Patented May 11, 1881 I ifiinesses;

'M/ ZM N PETERS. Pholouthn nphlr. Wnhhgion. II Q UNITED STATES PATENTOFFICE.

HERBERT W. CHAPMAN, OF NEWARK, NEW JERSEY.

FOOT-PRESS FOR JEWELERS, 800.

SPECIFICATION forming part of Letters Patent No. 241,617, dated May 17,1881..

Application filed August 30,1880. (No model.)

To all whom it may concern Be it known that 1, HERBERT W. CHAP- MAN, ofNewark, in the county of Essex and State of New Jersey, have invented anew and useful Improvement in Foot-Presses for Jewelers, 8210., of whichthe following is a specification.

My invention relates to presses such as are used by jewelers and othersfor punching, stamping, and embossing metals, and are operated byfoot-levers.

The object of the invention is to provide an improved and convenientdevice accessible above the press-table for quickly clamping andreleasing the die-bolster, in order to facilitate the manipulation ofexchanging and readjusting the lower or female die, and to avoid theliability of inaccurate adjustment and wear of the bolster incurred bytheold mode of fastening by bolts and nuts.

In the accompanying drawings, Figure 1 represents a front view of afoot-press embodying myinventiou, and partly in section through the lineas m of Fig. 2, the bolster-bed being furtherin part broken away throughthe line w 00 of Fig. 2. Fig. 2 represents a side elevation of thepress, partly in section, through the line 3/ y of Fig. 1.

' Similar letters of reference indicate corresponding parts.

A designates the frame of the press; B, the table; 0, the slideholdingthe male die; D, the foot-lever by means of which the slide 0 isoperated, and E the link connecting the short arm of the lever D withtheslide G. I

F is the bolster-bed, secured in any suitable manner upon the table B.

G is the bolster, having a bevel-edged slot in its face, as usual, inwhich the female die is inserted, and end flanges, g, for clamping it tothe bed.

H are the clampingbolts. These are arranged to slide vertically in holesmade through the bed F and table B, and their shanks are surrounded byspiral springs I, acting between the table and the head of (or ashoulder on) the upper end of the shanks, to raise the bolts when theclamping pressure is removed. The bolts H are side-headed, or, in otherwords, ahori zontal projection, h, is formed on only one side of theshank, and the bolts are arranged with their heads h toward each otherand just above the flanges g, so that when the bolts descend the flangesg of the bolster Gr will be clamped to the bed F by the heads h. Toaccomplish this, to the lower end of each bolt, H, projecting below thetable B, is pivoted by a pin, j, a lever, J, having a set-screw, K,through its forward end, to adjust its distance from the under side ofthe table, and a slot or groove, n, in the upper side of its rear end,in which groove the face of a cam, L, is arranged to work, so as toalways be kept in Working contact with the lever J. The working radiusof the cam increases from a to b, the throw being equal to thedifference between the radii at those two points. The two cams L aresecured by setscrews m upon a horizontal shaft, M, having its hearing orbearings in the bed F, and to one end of the said shaft, projectingbeyond the bed, is attached a lever, O, by which the shaft is turned tooperate the cams L. To prevent the cams from being turned out of thegroove '12 they are provided each with a projection or shoulder, l,which at completed throw of the cam stops against the casting in the bedF, as shown in Fig. 2. The lever 0 being above the table, the operatorcan handle itwhile in full view of his dies, pulling it forward into theposition shown in the drawings when he wishes to make the bolts Hdescend and clamp the flanges g and bolster G to the bed F, and pushingit rearward when he wishes to remove the bolster to change dies. On therelease of cam-pressure the bolt-heads h are raised from contact withthe flanges g by the expansive force of the springs I.

The force or tightness of the grasp of the boltheads h upon the flangesg is regulated by the set-screw K, increasing when the said screw isbeing turned inward, and decreasing when it is being turned outward orunscrewed.

By this construction the bolts H are caused to slide in straight lines,and both act upon the flanges g simultaneously by moving the lever O,and no damage is caused to the bolster G by any turning play or lateralmovement of bolts and bolt-heads.

Having thus described myinventiou, what I claim as new, and desire tosecure by Letters Patent, is-

1. A die-press in which the bolster G is held by clamping devices H J L,operated by a lever, 0, arranged above the table B, substantially asspecified.

2. The combination of the bolster G, springpressed sliding bolts H,having adjustable levers J pivoted to their shanks, the cams L,cam-shaft M, and ban d-lever 0, arranged above the table, substantiallyas and for the purpose set forth.

3. The combination, with the side-headed sliding bolt H and the cam L,of the lever J, pivoted to the said bolt and provided with the endgroove, n,1"or retaining the cam-face in Working contact and prevent thebolt from turning, substantially as set forth.

HERBERT W. CHAPMAN.

Witnesses JOHN M. STELLE, A. W. ALMQVIST.

